A3-A3 anastomosis and superficial temporal artery-radial artery graft-A3 bypass to treat bilateral ACA steno-occlusive hemodynamic ischemia with cognitive and executive dysfunction: a technical note

Superficial temporal artery interposition bypass for the treatment of complex intracranial aneurysms: Flexible and creative options for flow preservation bypass

PURPOSE

Flow-preservation bypass is a treatment option for complex intracranial aneurysms (IAs) that cannot be managed with microsurgical clipping or endovascular treatment. Various bypass methods are available, including interposition grafts such as the radial artery or saphenous vein. Size discrepancy, invasiveness, and procedure complexity must be considered when using interposition grafts. We describe our experience of treating complex IAs using a superficial temporal artery (STA) interposition bypass.

METHODS

We retrospectively reviewed the medical records and operative videos of all patients who were treated for complex IAs at our center from January 2009 to December 2021 using cerebral revascularization. Clinical, radiological, and surgical findings of the cases that underwent STA interposition bypass were investigated.

RESULTS

Seventy-six bypass procedures were performed of which seven (9.2%) complex IAs were managed using STA interposition bypass. Of these 5 cases were of anterior cerebral artery, 1 of middle cerebral artery, and 1 of posterior inferior cerebellar artery aneurysm. There were no postoperative ischemic complications. Revision surgery for postoperative pseudomeningocele was performed in one case. The long-term bypass patency rate was 85.7% (6 out of 7) and good long-term aneurysm control was achieved in all cases, with a mean follow-up of 64 months.

CONCLUSIONS

When treating complex IAs, creative revascularization strategies are needed in selective cases for favorable outcomes. STA interposition graft bypass which can reduce the size discrepancy between the donor and recipient may be a less invasive, flexible, and practical option for treating complex IAs.

Anterior cerebral artery dissection for a patient with ipsilateral aplastic or twig-like middle cerebral artery: An illustrative case report

Background

An aplastic or twig-like middle cerebral artery (Ap/T-MCA) is a rare anomaly, which sometimes causes ischemic infarction. Collateral flow from the ipsilateral anterior cerebral artery (ACA) is important for patients with Ap/T-MCA. If ipsilateral ACA stenosis or occlusion occurs, a large infarction with a wider field than the ACA territory could happen. First, mechanical thrombectomy was performed for the right ACA near occlusion caused by arterial dissection with ipsilateral Ap/T-MCA in this case. Second, Wingspan stenting was performed for the right ACA restenosis.

Case Description

A 77-year-old female presented to the hospital with the left hemiparesis. We diagnosed a right ACA infarction caused by right ACA occlusion. Digital subtraction angiography showed right Ap/T-MCA and ipsilateral ACA near occlusion. Thrombectomy was performed, and recanalization was achieved with mild ACA stenosis. The lesion was the dissection due to angiographical finding. Two months after treatment, transient left hemiparesis occurred and right ACA stenosis progressed. Computed tomography perfusion showed hypoperfusion of the right hemisphere. Wingspan stenting was performed from the left internal carotid artery through the anterior communicating artery with an intermediate catheter. The patient was discharged without any neurological deficit.

Conclusion

We reported the first case of a patient who underwent Wingspan stenting for the right ACA dissection with Ap/T-MCA. Short-term follow-up and aggressive intervention should be considered for collateral pathway dissection with Ap/T-MCA because the symptoms can become serious. The patients with Ap/T-MCA should be cautious about the collateral pathway arterial changes in particular ipsilateral ACA due to the increasing hemodynamic stress.

STA-A3 Bypass Using Radial Artery Graft for Progressive Cerebral Infarction of Bilateral ACA Region after STA-MCA Bypass Surgery for Moyamoya Disease

Direct revascularization surgery, such as superficial temporal artery (STA)-middle cerebral artery (MCA) bypass, is effective in preventing ischemia and hemorrhage for moyamoya disease. On the other hand, when ischemia of the anterior cerebral artery (ACA) region progresses after ipsilateral STA-MCA bypass, it is difficult to perform revascularization from the viewpoint of the donor artery. A 55-year-old woman with right hemiparesis was diagnosed with cerebral infarction due to moyamoya disease. Left STA-MCA bypass was performed with no postoperative complications, but memory impairment and decreased motivation were observed 2 months after the operation. Magnetic resonance imaging and angiography revealed new infarction in the bilateral ACA area and deterioration in the signal intensity of bilateral ACAs. Revascularization of the bilateral ACA regions was considered necessary, but the left STA was already used in the previous surgery. Therefore, STA-radial artery (RA)-A3 bypass using RA graft combined with right STA-MCA bypass was performed. STA-A3 bypass using an RA graft may be the optimal treatment for ischemia of the ACA region that progresses after STA-MCA bypass.

One-stage Revascularization to the Ipsilateral Middle Cerebral Artery and Contralateral Anterior Cerebral Artery Territories

BACKGROUND

Patients with multiple intracranial atherosclerotic stenoses often present with haemodynamic instability in two remote regions without a reciprocal vascular network. In this situation, revascularisation to each region may be required.

METHODS

In this report, two patients who had coexisting unilateral middle cerebral artery (MCA) and contralateral anterior cerebral artery (ACA) territory ischemia were treated by using ipsilateral superficial temporal artery (STA)-radial artery graft (RAG)-contralateral A3 bypass and ipsilateral STA-MCA bypass in one stage.

RESULTS

Postoperatively, the bypass conduit was well established and the patients' haemodynamic instability was improved.

CONCLUSION

In patients with severe haemodynamic instability in the remote unilateral MCA and contralateral ACA regions, as in our two cases, ipsilateral STA-MCA and ipsilateral STA-RAG-contralateral A3 bypasses in one stage can be a treatment option.

Superficial temporal artery lengthening technique to prevent postoperative wound complications in direct revascularization to the anterior cerebral artery for Moyamoya disease

BACKGROUND

Neurocognitive dysfunctions or psychomotor symptoms of Moyamoya disease may improve after direct revascularization to the anterior cerebral artery (ACA). However, long-distance harvest of the frontal branch of the superficial temporal artery (STA) is needed to reach the cortical ACA, frequently resulting in postoperative wound complications. To solve this problem, we devised a novel method (STA lengthening technique). In this study, we compared the STA lengthening technique and the conventional method regarding postoperative wound complications.

METHODS

Twenty-five patients who underwent STA-ACA direct bypass from December 2016 to October 2021 were retrospectively reviewed, and postoperative wound complications were recorded. Magnetic resonance angiography was performed to evaluate the patency of the bypass to the ACA and postoperative development of collaterals to the skin flap.

RESULTS

Thirty-eight hemispheres (new method [n = 12] vs. conventional method [n = 26]) were treated. Wound complications occurred in 12 surgeries (46%) of the conventional method, and none (0%) of the new method. The anastomosis with the cortical ACA was patent in all surgeries. Postoperative development of collaterals to the skin flap was confirmed after all surgeries (100%) in the new method, whereas after only five surgeries (20%) in the conventional method.

CONCLUSION

The STA lengthening technique can enable to preserve the collateral circulation to the skin flap postoperatively, resulting in good wound healing.

Revascularization to the ACA: effectiveness and variation of the STA-RAG-A3 bonnet bypass

BACKGROUND

The effectiveness of bypass surgery in patients with atherothrombotic ischemia in the anterior cerebral artery (ACA) domain remains unclear. In this study, three cases with ischemia in the ACA territory underwent revascularization surgery using superficial temporal artery (STA)-radial artery graft (RAG)-A3 (pericallosal artery) bonnet bypass. Herein, we discuss the effectiveness and variations of this approach.

METHODS

Among 182 consecutive patients with atherothrombotic ischemic stroke admitted to the NTT Medical Center, Tokyo, from April 2017 to May 2021, three patients with hemodynamic insufficiency in the extensive ACA territory beyond the recent infarct area were treated using STA-RAG-A3 bonnet bypass.

RESULTS

One patient with bilateral severe cerebral blood flow (CBF) deficiency required additional A3-A3 and STA-middle cerebral artery single bypass in conjunction with STA-RAG-A3 bypass. There were no complications associated with the surgical procedure. The patients' hemodynamic study results and neurocognitive performances improved dramatically after surgery.

CONCLUSION

Our results suggest the efficacy of STA-RAG-A3 bypass for atherothrombotic ACA ischemia. However, because the number of cases was too small to generalize our results, more cases and thorough pre- and postoperative hemodynamic studies are necessary to prove the validity of the approach.

Tailored Communicating Bypass for the Management of Complex Anterior Communicating Artery Aneurysms: "Flow-Counteraction" In Situ Bypass and Interposition Bypass Using Contralateral A2 Orifice as Donor Site

BACKGROUND

The use of bypass surgery for anterior communicating artery (ACOM) aneurysms is technically challenging. Communicating bypass (COMB), such as pericallosal artery side-to-side anastomosis, is the most frequently used and anatomically directed reconstruction option. However, in many complex cases, this technique may not afford a sufficient blood supply or necessitate sacrificing the ACOM and the eloquent perforators arising from it.

OBJECTIVE

To evaluate tailored COMB and propose a practical algorithm for the management of complex ACOM aneurysms.

METHODS

For 1 patient with an aneurysm incorporating the entire ACOM, conventional in Situ A3-A3 bypass was performed as the sole treatment in order to create competing flow for aneurysm obliteration, sparing the sacrifice of eloquent perforators. In situations in which A2s were asymmetric in the other case, the contralateral A2 orifice was selected as the donor site to provide adequate blood flow by employing a short segment of the interposition graft.

RESULTS

The aneurysm was not visualized in patients with in Situ A3-A3 bypass because of the "flow-counteraction" strategy. The second patient, who underwent implementation of the contralateral A2 orifice for ipsilateral A3 interposition bypass, demonstrated sufficient bypass patency and complete obliteration of the aneurysm.

CONCLUSION

The feasibility of conventional COMB combined with complete trapping may only be constrained to selected ideal cases for the treatment of complex ACOM aneurysms. Innovative modifications should be designed in order to create individualized strategies for each patient because of the complexity of hemodynamics and the vascular architecture. Flow-counteraction in Situ bypass and interposition bypass using the contralateral A2 orifice as the donor site are 2 novel modalities for optimizing the advantages and broadening the applications of COMB for the treatment of complex ACOM aneurysms.

In Situ Side-to-Side Pericallosal-Pericallosal Artery and Callosomarginal-Callosomarginal Artery Bypasses for Complex Distal Anterior Cerebral Artery Aneurysms: A Technical Note

BACKGROUND

Despite surgical and endovascular technical improvements over the last decades, the treatment of complex aneurysms of the distal anterior cerebral artery (ACA) is very challenging for both vascular neurosurgeons and interventional neuroradiologists. Furthermore, the interpersonal anatomic variability requires, most of the time, a tailored planning.

OBJECTIVE

To describe a novel technique of bypasses in the territory of ACA to protect the brain territory distal to the aneurysm.

METHODS

A 53-yr-old male with a large complex fusiform aneurysm of the left distal A2 segment of the ACA, involving the origin of the callosomarginal and pericallosal arteries, was judged not suitable for a single procedure (endovascular or neurosurgical). Two side-to-side bypasses were performed in a single surgery to connect the pericallosal and callosomarginal arteries of both sides, distally to the aneurysm. Subsequently, an endovascular embolization of the aneurysm was achieved with coils.

RESULTS

The patency of the microanastomoses, performed in the anterior interhemispheric fissure, was positively evaluated intraoperatively with indocyanine green and fluorescein videoangiography. The aneurysm sac, together with proximal A2 segment, was completely occluded with platinum coils. At the last follow-up, computed tomography angiography confirmed the patency of both bypasses, without any sign of aneurysm recanalization. The patients never complained of any focal neurological deficits or worsening of clinical status.

CONCLUSION

We present an elegant and innovative solution to completely protect the distal ACA territory in cases of complex aneurysm involving the origin of both callosomarginal and pericallosal arteries.

Anterior Cerebral Artery Bypass for Complex Aneurysms: Advances in Intracranial-Intracranial Bypass Techniques

BACKGROUND

Anterior cerebral artery (ACA) bypasses for complex aneurysms are infrequently performed, yet previous experience demonstrates the importance of intracranial-intracranial bypasses. Here we describe technical advances in intracranial-intracranial bypass techniques and their clinical results.

METHODS

Twenty-three patients with complex aneurysms requiring ACA bypasses were retrospectively studied. Ten patients were treated in period 1 (1997-2013) and 13 in period 2 (2014-2018).

RESULTS

There were 3 precommunicating, 8 communicating, and 8 postcommunicating ACA aneurysms, plus 4 middle cerebral artery aneurysms. ACA in situ bypass was the most commonly performed (9 patients; 39%). The classic left A3 ACA-right A3 ACA in situ bypass was performed in 5 patients, but 3 new in situ variations emerged in period 2: left pericallosal artery (PcaA)-right PcaA (n = 1), left callosomarginal artery (CmaA)-right CmaA (n = 2), and left CmaA-right A3 ACA (n = 1). The sole reimplantation in period 1 was the ipsilateral and vertical PcaA-CmaA reimplantation, whereas reimplantations in period 2 were contralateral and horizontal (left PcaA-right PcaA and right A3 ACA-left anterior internal frontal artery). The A1 ACA was used as a donor only in period 2 in 4 patients with middle cerebral artery bifurcation aneurysms. Bypass patency was 91%, and 21 patients (91%) improved or remained at neurologic baseline (mean [standard deviation] follow-up duration, 26 [8.2] months).

CONCLUSIONS

ACA bypass techniques continue to evolve with the addition of several variations. These variations push bypass techniques beyond the standard constructs and add important alternatives to our bypass arsenal.

STA-Distal ACA Bypass Using a Contralateral STA Interposition Graft for Symptomatic ACA Stenosis

Intracranial arterial stenosis usually occurs due to atherosclerosis and is considered the most common cause of stroke worldwide. Although the effectiveness of bypass surgery for ischemic stroke is controversial, the superficial temporal artery to the middle cerebral artery bypass for ischemic stroke is a common procedure. In our report, a 50-year-old man presented with sudden-onset left side weakness and dysarthria. An angiogram showed significant stenosis in the junction of the right cavernous-supraclinoid internal carotid artery and right pericallosal artery. Symptoms altered between improvement and deterioration. Magnetic resonance imaging showed a repeated progression of anterior cerebral artery (ACA) infarction despite maximal medical therapy. We performed a STA-ACA bypass with contralateral STA interposition. Postoperative course was uneventful with no further progression of symptoms. Thus, bypass surgery may be considered in patients with symptomatic stenosis or occlusion of the ACA, especially when patients present progressive symptoms despite maximal medical therapy.

STA-ACA bypass using the ipsilateral free STA graft as an interposition graft and A3-A3 anastomosis for treatment of bilateral ACA steno-occlusive ischemia

BACKGROUND

Anterior cerebral artery (ACA)-related ischemia is a rare entity in patients with atherosclerosis. Some surgical treatments are reported to date.

METHOD

We present the modification of intracranial-intracranial and intracranial-extracranial bypasses for symptomatic bilateral ACA steno-occlusive disease. The A3-A3 bypass followed by the superficial temporal artery-ACA bypass using the ipsilateral free superficial temporal artery graft is useful without harvesting of the radial artery.

CONCLUSION

Bilateral ACA steno-occlusive induced ischemia can be treated with tailored bypass procedures.

Technique for rerouting a bridging vein that hinders the anterior interhemispheric approach: a technical note

BACKGROUND

The frontal bridging vein, which is the venous drainage route of the frontal cortex into the superior sagittal sinus (SSS), sometimes poses an obstacle in the anterior interhemispheric approach during surgery for anterior cerebral artery aneurysms. Although severe complications including venous infarction or edema due to damage to the bridging vein are well known, only a few reports have discussed how to avoid venous injury when we must sacrifice the bridging vein to obtain an appropriate surgical field. This report describes a microvascular technique performed in two patients who underwent rerouting of the bridging vein to obtain an appropriate anterior interhemispheric surgical corridor to treat a ruptured anterior cerebral artery aneurysm. The hindering bridging vein was resected from the entrance to the SSS and anastomosed toward the adjacent cortical vein.

METHODS

A 65-year-old male and a 43-year-old male were admitted to our hospital for sudden headache. Computed tomography, magnetic resonance angiogram, or digital subtraction angiography demonstrated a subarachnoid hemorrhage and an anterior cerebral artery aneurysm in both patients. In both cases, a relatively robust bridging vein, which appeared problematic to sacrifice, was draining into the SSS, resulting in a limited surgical corridor. Thus, we performed cortical vein reconstruction, and the aneurysms were successfully clipped under a wider surgical view.

RESULTS

We confirmed completed clipping without postoperative venous complications. One patient demonstrated patency of reconstructed venous flow by digital subtraction angiography. No apparent cognitive impairment was seen in either patient.

CONCLUSIONS

This technique may be useful for obtaining an appropriate surgical corridor when the frontal bridging vein may be damaged.